<template>
  <div>
      <div v-for="(item,index) in arr" :key="index" style="display:inline-block">
          <input type="checkbox" v-model="num" :value="item">
          <span>{{item}}</span>
      </div>
      <p>你选中的元素，累加的和为：{{allNum}}</p>
  </div>
</template>

<script>
export default {
    data () {
        return {
            arr:[9, 15, 19, 25, 29, 31, 48, 57, 62, 79, 87],
            num:[]
        }
    },
    computed:{
        allNum(){
            return this.num.reduce((sum,val)=>{
              return (sum += val)
            },0)
        }
    }
}
</script>

<style>

</style>